1. Field of the Invention
The present invention relates to a portable terminal, and more particularly to, a method and apparatus for gauging a battery in a portable terminal of the type having an active matrix organic light emitting diode (AMOLED) display.
2. Description of the Related Art
A smart phone usage has been increasingly growing as it provides more various functions when compared to a conventional phone.
As the amount of time the portable terminal is utilized by the user increases, an amount of battery consumed by the portable terminal increases. To this end, the portable terminal may display, to the user, a residual quantity of the battery via an indicator bar and the like, so as to enable the user to control the use of the portable terminal.
Recently, a controlling device of the portable terminal, for example, a controller or a central processing unit (CPU), has been developed to utilize multiple cores or processors, thus the size of a displaying device has been increased which in turn causes more battery consumption. Especially, the battery consumption due to the displaying device has been increasingly growing. Hence, the amount of the battery consumed for driving the displaying device may need to be accurately measured first, so as to accurately inform the user of the residual quantity of the battery.
In general, a process of measuring the residual quantity of the battery of a portable terminal may be referred to as battery gauging. Conventionally, battery gauging has been performed by converting an analog voltage value of the battery into a digital voltage value through use of an analog-to-digital converter (ADC) included in the controlling device.
The portable terminal may need to include a displaying device having a high resolution and definition, for example, an AMOLED display. The AMOLED display may provide a wide angle of view, a clear color, and the like. However, the AMOLED display has a drawback in that it consumes a different amount of power for each color. That is, the portable terminal equipped with the AMOLED display may have a rapid change in power consumption for each color represented by the AMOLED display. Accordingly, when the portable terminal performs battery gauging through use of the ADC included in the controlling device, battery gauging may not be accurately performed. Consequently, when the battery gauging is inaccurate, the residual quantity of the battery may be inaccurately displayed to the user.
To overcome the drawbacks, the portable terminal equipped with the AMOLED display as a displaying device may include a separate battery gauging device, for example, a gauge integrated circuit (IC) chip, so as to perform battery gauging by reflecting that a power consumption rate of the displaying device is rapidly changed. However, the separate battery gauging device may require a separate space in which the separate battery gauging device is to be contained. As such, it may adversely affect the cost and the design of the portable terminal, for example, a size and a thickness of the portable terminal.
Accordingly, there is a need for a portable terminal equipped with the AMOLED display to perform the battery gauging accurately without using the separate battery gauging device.